DNTP study spotlights the hidden harm of crude oil refinement
Inhalation of a hazardous compound produced during crude oil refining causes wide-ranging health problems in rodents, according to researchers from the NIEHS Division of the National Toxicology Program.
Ethyltoluenes are isolated during crude oil refinement for use in gasoline and commercial products. Exposure to these environmental contaminants, which are widespread in the air, can occur both occupationally and in the general population. However, critical toxicity data have been lacking.
To address this knowledge gap, the researchers explored the hazardous effects of the potent molecule 2-ethyltoluene (2-ET) in rats and mice. Inhalation of 2-ET for two weeks decreased survival and body weight and damaged the nasal tissue related to the sense of smell.
Pregnant rats exposed to higher concentrations of 2-ET produced fewer pups per litter, suggesting that the chemical may harm reproduction. In addition, their offspring showed liver damage and major decreases in body weight.
According to the authors, more research is needed to understand how 2-ET exposure causes toxicity and to clarify the relevance of these findings to humans. Although there are some estimates of ethyltoluenes in the environment, internal measures of human exposure have not been well documented. (JW)
Citation: Huang MC, Willson CJ, Jaligama S, Baker GL, Singer AW, Cao Y, Pierfelice J, Mutlu E, Burback B, Xie G, Malarkey DE, Sparrow B, Ryan K, Stout M, Roberts GK. 2021. Whole-body inhalation exposure to 2-ethyltoluene for two weeks produced nasal lesions in rats and mice. Inhal Toxicol 33(9-14):334–346.